THE CONSEQUENCE OF DELAYED VERSUS IMMEDIATE NERVE REPAIR ON THE PROPERTIES OF REGENERATING SENSORY NERVE-FIBERS IN THE ADULT-RAT

Transected saphenous neurones were allowed to regenerate for 3 months via distal stumps of sural nerve following an immediate or a 3 month d elayed repair. The number of DRG neurons surviving following the 3 mon ths regeneration period were approximately 60% of normal after both im mediate and delayed repair. The percentage of DRG cell bodies identifi ed by the application of Fluro-gold proximal to the repair site and im munopositive for SP, CGRP and galanin was increased following both ear ly and delayed repair compared to baseline values. These values were n ot significantly different for early repair compared to late repair. S imilarly, peripheral measurements of SP in the proximal stump of saphe nous nerve (by radioimmunoassay) were not significantly different betw een models with primary repair compared to delayed repair. These resul ts suggest that the intrinsic regeneration properties of primary senso ry neurones are not impaired when repair is delayed.